Floodlight housing and support



Jul 7, 1970 Filed April 19, 1967 3 Shocks-Sheet. 1

"l| mi iNVENTOR HENRY S. JACOBS ATTORNEY July 7, 1970 H. s. JACOBS 7 5 3v FLOODLIGHT HOUSING AND SUPPORT Filed April 19, 1967 3 Sheets-Sheet 2iilit l Z 14 INVENTOR HENRY S, JACOBS J y 97 H. s. JACOBS 3, 9,

FLOODLIGHT HOUSING AND SUPPORT Filed April 19. 1967 I 3 Sheets-Sheet 5INVENTOR HENRY s. JACOBS ATTORNEY United States Patent Us. (:1. 24o-3 3Claims ABSTRACT OF THE DISCLOSURE A floodlight housing includes anelectrical socket that is secured either to a single threaded shaftwhich extends through an opening in the rear end of an elongatedenclosure and is held against rotation, or to a pair of spaced screwswhich extend through two holes in the rear end of the enclosure. Bytightening nuts on the single threaded shaftor on the pair of screws,the socket and lamp bulb therein are drawn inwardly and the flared sidesof the lamp bulb are seated against a cushioning rubber gasket disposedabout the inner periphery of the enclosure. A polished, thin-Wallreflector portion of the enclosure flares outwardly beyond the lens endof the lamp bulb. The housing is supported on a U-shaped leaf spring,formed of unbonded laminations, which is attached at the ends of itsarms to diametrically opposed points on the enclosure. A flanged bracketis disposed within the U-shaped leaf spring, and the leaf spring andbracket are both secured to a base at their bottoms. A short biasingleaf spring is disposed between the bracket and the U-shaped leaf springto normally hold the lower ends of the arms of the U-shaped leaf springaway from the bracket.

BACKGROUND OF THE INVENTION This invention relates to floodlights, andparticularly to a floodlight housing and support adapted to protect thefloodlight lamp bulb from the effects of vibrations and shock leads.

Floodlights find numerous applications where a high degree ofillumination is required, and some of these applications subject thesealed beam, internal reflector type lamp bulbs commonly used in suchfloodlights to unusual strains due to shock loads and vibrations. Forexample, floodlights of the type considered herein are widely used onmobile construction equipment such as cranes, shovels, tractors, wellrigs, etc., for operation of the equipment at night. The continuousvibration and large shock loads which are encountered in suchapplications will cause damage to the filament of the lamp bulb ifprovision is not made for dampening the eflects of both vibrations andshock loads.

Floodlights normally include a housing for the lamp bulb that mounts anelectrical socket either of the threaded or bayonet type. It has beenpreviously suggested that the electrical socket should be spring mountedin the enclosure of the housing in such a manner that it is urgedrearwardly of the enclosure. The lamp bulb is thereby forced to seatitself against a seal disposed along the inner periphery of theenclosure adjacent its open forward end. The purpose of such aconstruction is to lock the lamp bulb within the enclosure of thehousing and also to prevent the natural elements from damaging theelectrical connections and structure within the enclosure. Onedisadvantage of such construction is that it is diflicult to insert anew lamp bulb into the socket because there is no resistance againstwhich the installer can work. That is, since the electrical socket isurged rearwardly by springs, any attempts to insert the bulb will simplyadd to the effects of the springs and move the socket rearwardly. Afurther disadvantage is that the locking force holding the bulb in placeis dependent solely on the spring force and cannot be varied.

To completely protect against the effects of vibration and shock, notonly should the lamp be locked within the housing, but the support ofthe housing on the equipment should dampen the effects of vibration andshock. Previous attempts in this direction have required the use ofcomplex, expensive constructions.

SUMMARY OF THE INVENTION According to the invention, there is provided afloodlight housing in which the floodlight lamp bulb can be locked inplace within an elongated enclosure against a cushioning seal, therebyprotecting the electrical connections and the internal structure of thehousing from the eifects of the natural elements. This result isaccomplished by providing means by which the electrical socket can bemanually moved forward in the enclosure for the insertion of a lamp bulband then drawn inwardly of the enclosure to a desired amount to have theflared sides of the lamp bulb seat against an annular sealing means. Thesocket and lamp bulb ferrule can be either a screw type or a bayonettype. The housing may also include an outwardly flared thin-walledreflector portion of the enclosure which has its inner surface polishedand which extends beyond the lens end of the lamp bulb for protection ofthe lamp bulb, for dissipation of heat from the housing, and to increaseillumination. Also, according to the invention, there is provided asupport for a floodlight housing which will dampen shock loads andvibrations to protect the filament of the lamp bulb. The supportincludes a U-shaped leaf spring of simple and economical constructionwhich is attached at its ends to diametrically opposed points on thehousing and which is secured to a base at its bottom to provide aresilient support for the housing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a wide view in elevation ofone embodiment of floodlight housing and support in accordance with theinvention. FIG. 2 is a front view of the floodlight housing and supportof FIG. 1 with portions of the housing broken away and with portions ofthe support shown in cross section for clarity of illustration. FIG. 3is a view in horizontal section taken in the plane of the line 33 ofFIG. 2. FIG. 4 is a view in vertical section taken in the plane of theline 44 of FIG. 3. FIG. 5 is a view in horizontal section of a secondembodiment of floodlight housing in accordance with the invention.Finally, FIG. 6 is a view in vertical section taken in the plane of theline 6-6 of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In one embodiment, a sealedlbeam, internal reflector type lamp bulb 10 is mounted in a housingincluding a cast aluminum enclosure indicated generally by the referencenumeral 11. The enclosure 11 is formed in a generally bullet shape whichtapers from a minimum at its closed rear end to an annular step 12formed on its inner periphery, and then outwardly therefrom in anoutwardly flared, thin-wall reflector portion 13. An electrical socket14 is disposed within the enclosure 11 towards the rear thereof. Thesocket 14 is secured to one end of a threaded shaft 15 which projectsthrough an opening 16 in the rear end of the enclosure 11, and leads 17for the socket 14 extend through a grommet 18 in an opening in the sideof the enclosure 11. Laterally projecting means in the form of ahexagonal nut 19 is nonrotatably secured to the shaft 15 and is slidablyreceived within an elongated passage 20 formed in an integral hubportion 21 extending inwardly from the rear end of the enclosure 11. Thepassage 20 is formed concentric with the opening 16 through theenclosure 11 and is of a hexagonal shape to mate with the nut 19 (seeFIG. 4).

A wing nut 22 is threadedly received on the projecting end of the shaft15. A short compression spring 23 is biased between a pair of washers 24which respectively bear against the exterior of the rear end of theenclosure 11 and the wing nut 22.

An annular rubber gasket 25 is comented in place On the step 12. Thelamp bulb 10, when secured in the electrical socket 14, is adapted toseat and seal against such rubber gasket 25.

To insert the lamp bulb within the housing, the wing nut 22 is loosenedand the shaft 15 is forced through the opening 16 in the enclosure 11.This will move the socket 14 far enough toward the open end of theenclosure 11 so that the lamp bulb 10, when held in the hand, can beeither screwed or twisted into the socket 14. The socket 14 will notrotate as the lamp bulb 10 is being inserted because of the engagementof the hexagonal nut 19 within the mating passage 20. When the lamp bulb10 has been placed into electrical contact within the socket 14, theshaft 15 is released and the compression spring 23 urges the socket 14and the lamp bulb 10 rearwardly to seat theoutwardly flaring sides ofthe lamp bulb 10 against the rubber gasket 25. The lamp bulb 10 islocked in place against the gasket by tightening the wing nut 22 in adesired amount. To remove the lamp bulb 10 from the housing it is onlynecessary to again loosen the wing nut 22 and move the shaft 15, socket14 and lamp bulb 10 forward. The use of the compression spring 23increases the sensitivity and range of locking of the lamp bulb withinthe housing. Although desirable, the compression spring 23 can beeliminated.

The gasket 25 is large and soft to cushion the lamp bulb 10 within thehousing and to prevent the lamp bulb from Working out of the socket.Various types of rubber are usable, and it has been found practical touse a closed cell foam or sponge rubber which resists temperatures up to175 Fahrenheit. The reflector portions 13 of the enclosure 11 willfunction to dissipate heat produced by the lamp bulb It This, coupledwith the use of a high thermal conductive material such as aluminum forthe enclosure 11, reduces the temperature in the line of contact betweenthe lamp bulb 10 and the gasket 25 to a point where the use of rubbercan be tolerated. For very high wattage lamps, or where a large numberof lamps are closely spaced together or otherwise subejcted to unusuallyhigh ambient temperatures, silicone rubber may be used. The innersurface of the reflector portion 13 is polished to present an additionalreflecting surface which substantially increases the distance ofeffective illumination. By extending the reflector portion 13 beyond thelens of the bulb 10, a further degree of protection is afforded to thebulb 10.

The support for the floodlight housing includes a base 26 having boltholes 27 at each of its four corners to receive anchor bolts 28 tosecure the base 26 to a working surface (see FIG. 1). The housing isattached to the base 26 by a U-shaped leaf spring 29 which, in thepreferred embodiment, comprises three unbonded laminations of springsteel 30. The leaf spring 29 is disposed about a U-shaped bracket 31having outwardly turned flanges 32 which define lateral limits for theleaf spring 29. The free ends of the spaced arms of the leaf spring 29are connected to the enclosure 11 at diametrically opposed, parallel,flat seating surfaces 33 formed on enlargements of the cast enclosure11. The connection of the U-shaped leaf spring 29 to the enclosure 11 isaccomplished by mounting bolts 34 that extend through openings in theenclosure 11. A large washer 35 is disposed against the outer surface ofthe end of each arm of the leaf spring 29, and a nut 36 together with apair of lock washers 37 releasably hold the large washer 35 and theU-shaped leaf spring 29 to the enclosure 11. An acorn nut 38 protectsthe exposed end of each of the mounting bolts 34. By loosening the nuts36, the housing can be pivoted within the support to change the aim oflamp bulb 10.

The laminations 30 comprising the leaf spring 29 and the bracket 31 aresecured to the base 26 by a support bolt 39 which passes upwardlythrough an opening in the base 26 and receives a spacer nut 40 and thenpasses through holes in the laminations 30 and in the bracket 31 andreceives a locking nut 41. Suitable lock and spacing washers areprovided on the support bolt 39.

A short biasing leaf spring 42 is disposed between the underside of thebracket 31 and the upper surface of the U-shaped leaf spring 29. Thisbiasing leaf spring 42 is stiffer than the laminations 30 and forces thelaminations 30 away from the bracket 31 adjacent the sides of thebracket. The U-shaped bracket 31 is dimensioned at its ends so that theU-shaped leaf spring 29 will press lightly on such ends.

The life of the lamp filament is a function of the filament supportwithin the lamp and the shock to which it is subjected. The inertia ofthe housing is many times that of the lamp bulb 10 alone. By floatingthe entire lamp bulb and housing on the spring support described, it 18possible to dampen shock loads and vibrations before they reach the lampbulb and its heated filament. This eliminates the necessity of usingspecial and expensive filament mountings.

The inertia of the housing tends to resist motion change. When the base26 moves suddenly downward with respect to the housing, only a portionof this movement is transmitted to the housing. The difference is takenup by the progressive bending of the laminations 30 with a decrease inthe clearance between the bracket 31 and the laminations 30. Ifcushioning in this direction is not needed, the biasing leaf spring 42can be omitted.

When the base 26 moves suddenly upward, the housing tends to remainstationary, thereby causing the laminations 30 to be pushed downwardlyand bulged outwardly. Lateral movement between the housing and the baseis taken up by bending of the laminations 30 between the ends of thebracket 31 and the attachments of the laminations 30 to the housing.

If sudden fore and aft movement of the working surface is a problem, theflanges 32 of the bracket 31 can be omitted so that the laminations 30are free to flex in the longitudinal direction of the housing. Even withthe flanges 32, some fore and aft movement is permitted by clearancebetween the flanges 32 and the edges of the laminations 30.

An alternate embodiment of a floodlight housing is illustrated in FIGS.5 and 6. The enclosure 43 is generally similar to the enclosure 11 ofthe first embodiment except that it has a flat rear end 44 provided onits inner surface with a pair of spaced, inwardly projecting lugs 45. Ahole 46 extends through each lug 45 and the rear end 44. The electricalsocket 47 has a pair of screws 48 received in openings normally providedtherefor, and the screws 48 are restrained against rotation by havingtheir heads cemented in place. The screws 48 project through the holes46 and receive wing nuts 49 which bear against the outer surface of therear end 44. The rubber gasket 50, which may be made hollow forincreased resilience, is adapted to seat against the outwardly flaringsides of the lamp bulb.

To replace bulbs within the embodiment of FIGS. 5 and 6, it is necessaryonly to loosen the wing nuts 49 upon the screws 48 so that the socket 47can be moved outwardly to release the lamp bulb from the rubber gasket40. Whether the lamp bulb has a screw or bayonet type ferrule, thescrews 48 will prevent rotation of the electrical socket 47 when thebulb is rotated. Once a neW bulb is inserted the wing nuts are tightenedto draw the electrical socket 47 inwardly to seat the bulb against therubber gasket 50. The lugs 45 provide a positive stop to the inwardtravel of the electrical socket 47.

Of course, this alternate embodiment of fioodlight housing can bemounted on the support previously described.

It will be seen from the foregoing description that the floodlighthousing and support of this invention provides an excellent, thoughrelatively simple and economical, means by which the sealed beam lampbulb of the Hood light can be protected against shock loads andvibrations. By locking the lamp into the housing, the inertia of thehousing aids the protection of the filament of the lamp and preventsvibrations from loosening the lamp in the electrical socket. The springsupport for the lamp effectively dampens vibrations and shocks.

Even though the lamp bulb is effectively locked within the housing, itcan be easily released and removed. New lamp bulbs can likewise beinserted with case.

While preferred embodiments of the invention have been described indetail to illustrate the invention, it will be apparent to personsskilled in the art that changes can be made in the embodiments shownwithout departing from the scope of the invention.

I claim:

1. A fioodlight housing for a fioodlight lamp bulb which increases indiameter from its base toward its lens end, said housing comprising: anelongated enclosure open at its front end and having enclosing sides anda closed rear end provided with a hole and an elongated passage, saidenclosure including an inner peripheral seat portion of a diameter lessthan the maximum diameter of said lamp bulb; annular cushion sealingmeans disposed on said seat portion; an electrical socket adapted toreceive the base of said lamp bulb and disposed within said enclosuretoward the rear end thereof; a threaded member mounting said socket andprojecting through said hole in the rear end of said enclosure; a nut onthe projecting portion of said threaded member, said nut being adaptedto work against the exterior surface of said rear end of said enclosurewhereby said nut may be loosened to move said threaded member and sockettowards said open front end of said enclosure for insertion of said lampbulb in said socket and whereby said nut may be tightened to draw saidlamp bulb and socket into said enclosure and seat said lamp bulb againstsaid cushion sealing means; and laterally projecting means non-rotatablyaffixed to said threaded member and adapted to mate with said passage toprevent rotation of said threaded member and socket throughout thelength of travel of said threaded member.

2. A support for a fioodlight housing comprising: a base; and agenerally U-shaped leaf spring rising from said base, said leaf springbeing formed of a plurality of identical, unbonded laminations of springmaterial, said leaf spring having its spaced arms connected adjacenttheir ends to diametrically opposed points on said housing and said leafspring being secured centrally at its bottom to said base.

3. A support for a floodlight housing comprising: a base; a generallyU-shaped leaf spring rising from said base, said leaf spring having itsspaced arms connected adjacent their ends to diametrically opposedpoints on said housing and said leaf spring being secured centrally atits bottom to said base; a generally U-shaped bracket disposed adjacentthe inner surface of said leaf spring and having the ends of its spacedarms terminating short of the ends of the arms of said leaf spring, saidbracket being also secured centrally of its bottom to said base; and ashort, biasing leaf spring disposed between said bracket and saidU-shaped leaf spring at the bottom thereof, said biasing leaf springhaving its ends bearing against the arms of said U-shaped leaf spring tospace such arms from said bracket.

References Cited UNITED STATES PATENTS 1,915,967 6/1933 Bailey 240-522,894,693 7/ 1959 Howarth 240- XR 2,933,273 4/ 1960 Koch 248-291 XR2,024,858 12/ 1935 Highfill 240-90 XR 2,511,937 6/1950 Natale 240-90 XR2,668,901 2/ 1954 Austin 240-3 2,699,491 1/ 1955 Sternaman 240-33,018,364 1/1962 Wenman 240-90 FOREIGN PATENTS 1,229,552 l/1960 France.

370,568 3/ 1923 Germany.

NORTON ANSHER, Primary Examiner R. P. GREINER, Assistant Examiner US.Cl. X.IR.

